My Sons 2001 Kx-65 Bogging Bad

[CROMANO]

Hello everyone, I was hoping maybe someone might be able to give me a hand in trying to figure out a problem I am having with my sons 65

The bike is bogging badly - we changed the plug & it still seems to be doing it.
It mostly does it on take offs, it sounds like to much gas is going into the carb at once? Like it floods out. I was told maybe it is the jets - I don’t know too much about bikes, but we just add 1 yama lube can to 5 gallons of gas. Is the gas to rich? I am clueless when it comes to this aspect of the bike & don’t know what it can be.

my son has just been feathering the clutch and revving it high to take off after he gets going it is fine it is just on take offs & when he lets go of the gas ?

Clueless dad looking for an answer - ha-ha

[MFolks]

What comes to mind is fuel filter clogged,air filter dirty? Did you remove the sparkplug and was the center electrode white(too lean) black(too rich) or light tan(just right)? Another check is to see if the carb float valve is set too high as this can cause bogging.

[CROMANO]

Thanks for the reply,

We changed out the air filter and put a new one in this weekend & we still had the bog.

I don’t know where the fuel filter is - I am sure I can find it - is it by the carb or inside the carb?

The float valve is inside the carb I am guessing.

The old spark plug was still working when we replaced it. It looked tan when we took it out.

Maybe it is the carb needs a cleaning - I don’t want to spend 85 bucks for my local dealer for a diagnostic- if I can figure this out.

I appreciate all your info and I hope I am not being a pain with my questions.

[MFolks]

The float is inside the float bowl under the carb and may be sticking due to crud in the needle that controls fuel level. On some carbs screws hold it in place and on others a spring clip. Turn the fuel off,remove the float bowl and look for crud in the bowl.

If this bike had a fuel filter it would be inline after the petcock or fuel valve on the tank. Was fuel comming out of the carb vent line? Go to the nearest auto parts store and buy a can of sea foam fuel system cleaner. A lot of people on this site have used it with great success. Another question is how dirty is the tank inside? Rust/crud can plug up jets in the carb. If they are plugged a rebuild kit may be one solution or remove the carb and clean it yourself.

If a person does not ask questions how are they expected to learn?

[hairbear65]

KX65s are known crank bearing eaters. To be sure...pull off the magneto cover for the flywheel....grab the flywheel and try moving it side to side...if there is play in it....the bike can be misfiring because when the flywheel spins the centrifucal(sp/) force on the flywheel is increased and therefore the play becomes excessive...that excessive play can cause the small metal plate on the flywheel to either come in contact with or change the air gap between the crankshaft sensor.

This is just and idea...and hopefully this isn't your problem.

Tom

[chase114]

The gas tank is plastic so there should be no rust. When somebody told you it sounds rich they were probably meaning jet size and not your fuel mixture. Does it run fine once he gets going? Did this problem just start?

The float may be sticking, try cleaning the carb. Has it be excessively hot where you are located? You my need to rejet. It was 100 degrees this weekend where we were racing and there was alot of bikes bogging on the line.

[hairbear65]

Also...

Some thing I've seen more than once in my lifetime..

BAD GAS!!

Bad gas cost me a track championship in 92'....by the time we figured it out my gate had dropped. The bike would idle, but bogged terribly when I opened the throttle.
Have you used this gas before?...(meaning the gas thats presently in the can)..Have you used this gas before in the bike.....or Did the problem start around the same time you purchased the new 5 gallons you say you mixed??

[CROMANO]

Thanks guys for all the feed back , I am going to clean the float bowl & check the fuel filter tonight.

Hairbear - the gas i been using 92 octaine & it is about 2 months old, it has been in the can in my garage. i am sure this has something to do with it. after i clean everything out with the a fuel system cleaner , i am going to start using racing gas.

chase - i live in san diego - we go to lake ellsinore mx park - it was about 98 degrees out there this weekend.

if you guys have any other suggestions please feel free to let me know- i want to say thank you for all your help so far.

i am going to start working on the bike tonight i will keep you guys posted.

if i cant figure this out - do you guys know any service guys who work out side of there shops for extra money - they would have to be in san diego of course.

[hairbear65]

You really don't need the race gas...can't hurt though.
2month old gas should still most likely be ok...

When I say bad gas...I mean right from the pump....the day you buy it...the bike or a vehicle won't run.
Another idea...plastic gas cans are permeaible (sp?)...meaning they have very small pours that allow the gas can to breath...thereby letting the gas go bad faster. Metal cans are much..much better.

tom

[Billy B]

I've had gas go bad in 2 months. As stated above no need for race gas. Unless you have had work done that would require race gas it is not necessary. Buy a ratio rite cup and only mix a couple gallons at a time, they sell em at most bike shops. I would also check the jetting. There is a good guide at the top of the forum page.